How do I set the width of a combobox to fit the entries in its list

You can iterate through the list to find the longest text extent using MeasureString, and then use this as the combobox width adding a fudge factor for the dropdown button.

	System.Drawing.Graphics g = comboBox1.CreateGraphics();
	float maxWidth = 0f;
	foreach(object o in comboBox1.Items)
	{
		float w = g.MeasureString(o.ToString(), comboBox1.Font).Width;
		if(w > maxWidth)
			maxWidth = w;
	}
	g.Dispose();
	comboBox1.Width = (int) maxWidth + 20; // 20 is to take care of button width